Method of forming drawbar yokes



1,567,352 L. L. WHITNEY 7 METHOD OF FORMING DRAWBAR YOKES Filed July 14, 1924 5 a: I l Ilij Z10 T455. 3 za i 1 H HP 11* l U50 1M1, w ll 1 w Z 4 6 L zo IQ; 5 27 Z56 J; as M I? Z7 i z: w in .m M II,

Patented Dec. 29, 1925.

- UNITED STATES PATENT OFFICE.

LOREN L. WHITNEY, OF HAMMOND, INDIANA, ASSIGNOR TO AMERICAN STEEL FOUNDBIES, OF CHICAGO, ILLINOIS, A CORPORATION OF NEW JERSEY.

METHOD OF FORMING DRAWBAR YOKES.

Application filed July 14, 1924. Serial No. 725,764.

To all whom it may concern Be it known that I, LOREN L. WVHITNEY, a citizen of the United States, residing at Hammond, in the county of Lake and State of Indiana, have invented certain new and useful Improvements in Methods of Forming Drawbar Yokes, of which the following is a specification.

Thisinvention relates to a new and improved method of forming draw bar yokes or the like and more particularly to a method of forming such yokes from blanks by a series of forging operations. Drawbar yokes as commonly c nstructed are U shaped in contour and are usually formed by welding together several elements.

It is an object of the present invention to provide a method of forming draw bar 'yokes by a. series of simple forging operations.

It is a further object to provide a method of forming a yoke which is a unitary structure without any welded joint.

It is an additional object to provide a method in which the yoke may be formed from a simple rectangular blank and which method is adapted for ready commercial production.

Other and further objects will appear as the description proceeds.

I have illustrated in the accompanying drawings the blanks used in the manufac ture and the various steps in the formation of the yoke, together with dies suitable for the forging operations.

In the drawings:

Figure 1 is a plan view of one end of a blank;

Figure 2 is a face view of Figure 1;

Figure 3 is an end view of the blank;

Figure 4 is a View similar to Figure 1, after the first forging operation;

Figure 5 is a face view of Figure 4;

Figure 6 is an end view of Figure 4;

Figure 7 is a view similar to Figure 1, showing the end of the blank after the second forging operation;

Figure 8 is a face view of Figure 7;

Figure 9 is an end view of Figure 7;

Figure 1O is a view similar to Figure 1, after the third forging operation;

Figure 11 is a face view of Figure 10;

Figure 12 is an end view of Figure 10;

Figure 13 is a view partly broken away showing the entire blank after both ends have been forged;

Figure 14 is a view of the blank after the bending operation;

Figures 15 and 16 show dies suitable for the operation; and

Figures 17, 18 and 19 show forging plun gers adapted to be used in connection with the dies.

In the carrying out of my method, the end of the blank as shown in Figures 1 to 3 is heated. The heated end of the blank 20 is then placed between the dies 21 and 22 shown in Figures 15 and 16, the blank being opposite the upper recesses 23 and 24 of the dies. The dies are brought together, the blank being clamped between the flat portion 25 of die 21 and the recess 24 of the adjacent die 22. The plunger shown in Figure 17 is then moved to bring its reduced portion 26 into the opening formed by the cooperating recesses 23 and 24. This plunger applies endwise pressure to the heated end of the blank and the blank is expanded laterally into the recess 23. The blank now assumes the form shown in Figures 4, 5, and 6, having the thickened end portion 27.

The heated blank end is next placed between the die recesses 28 and 29 of the dies and the plunger 30 shown in Figure 18 has its reduced portion 31 thrust into the end of the cavity formed by the die recesses and against the thickened end 27 of the blank. The force applied expands the end of the blank laterally filling the relatively deeper cavity 28. The blank now assumes the form shown in Figures 7 to 9 having the thickened end 32.

The heated end 32 is now placed in the lower recesses 33 and 34 of the dies, the offset face extending into recess 33. The reduced portion 35 of plunger 36 is now brought against the end of the blank and the portion 32 is further thickened as shown at 37 in Figure 10. Also, due to the shoulder 38 in the die recess 33, the lip 39 is formed on the end of the blank.

The opposite end of the blank is heated and treated in a manner similar to that just described. The blank now assumes the form shown in Figure 13. The blank is next bent to a U shape form as shown in Figure 14, with the thickened portions 37 and lip 39 opposite each other. The blank is noW formed to a complete draw bar yoke and may be drilled for any desired securing means.

I claim:

The method of forming draw or the like Which comprisesheating an end of a blank, placing said end in a die recess of given depth and upsetting said end to thicken it, then placing said end in another bar yokes .end of the blank, and bending the. blank into U-shape. r

Signed at Hammond, Indiana, this 9th day of July, 1924.

LoREN L. WHITNEY. 

